Contact tracing is the process of reconstructing the interactions of a sick person from the time they were infected until the time they were diagnosed. A case investigator reaches out to a person who has tested positive and helps them create a list of contacts they've recently been close to who may have been exposed. Their contacts are then notified about their potential exposure and are given recommendations to help slow down the spread of the virus. Contact tracing has typically been done manually. Manual contact tracing is a proven method and is highly effective. However, it requires a lot of time and resources. New tools can help scale and supplement manual contact tracing, such as digital contact tracing and exposure notification technology, like Covid Watch.
The Covid Watch app takes detective work out of the equation and is completely anonymous. This is not contact tracing. We use the Bluetooth feature on your smartphone to sense when you are near someone else with Covid Watch installed, however your location is always unknown. A log of instances when you were in close proximity to other users is stored solely on your phone. The people you’ve come in contact with will have a corresponding record on their phones. These logs are only stored for a few days, then are permanently deleted.
If either person tests positive for COVID-19, they can inform the app about their diagnosis. Without requiring them to remember whom they saw in the past two weeks, Covid Watch will automatically warn everyone they were in close proximity to about potential infection and encourage them to take action like getting tested or self-quarantining. We call this key intervention an ‘anonymous exposure notification.
Covid Watch is using technology to make it safer for us all to be together again. As COVID-19 testing becomes more prevalent and communities take steps to reopen, we need a system to reflect our real-world interactions accurately and provide actionable information as soon as the virus is detected. Actionable information provided in the Covid Watch App will vary based on your risk score, and may include information on where to get tested or a recommendation to self-quarantine. Anonymous exposure notifications, like those provided by Covid Watch, empower individuals and communities with the information they need to respond to potential infection and stop the spread.
The Covid Watch App works best when communities adopt it together, but it’s not necessary for everyone around you to have Covid Watch installed to help slow the spread of COVID-19. Even if a relatively small percentage of a community is using Covid Watch, it can still help slow down the spread. In general, each additional person using the app increases the speed with which individuals can act on information about their exposure risk and the steps they can take to keep their communities safer.
Bluetooth signals can sense who’s actually close to you and for how long. If you’re on the first floor of a tall building, and someone else is on the 15th, a Bluetooth signal would not log your interaction. That’s not true of other ways to view your location, like GPS.
Most importantly, your Bluetooth signal belongs to you and your phone. Using Bluetooth, your data is never stored centrally (“stored centrally” here means, for example, storing user data in a central master database managed by a government or private entity). Instead, random numbers that log your interactions via Bluetooth are stored solely on your own device.
Since we choose not to collect any location data due to privacy concerns, we don’t use GPS, so we can’t tell you where you were exposed. However, we will be able to tell you on which day you were exposed.
We recognize that this involves some privacy trade-offs, since if you receive an alert that you were exposed on a day where you were within six feet of very few people, you may be able to deduce who shared their test results.
We think the benefits of knowing when you were exposed outweigh the privacy risks of deduction.
Risk is calculated based on how close and for how long you were in close proximity to an infected person. Based on your risk score, you will be given actionable information for next steps. For example, low risk actionable information may recommend that you “monitor your symptoms for the next 14 days and call this public health number 555-555-5555 if you develop a cough for a free test”. High risk actionable information may recommend that you “quarantine away from your family/roommates for 14 days”.
Your local public health officials are closely monitoring testing for COVID-19. This testing is key to slowing the spread. It’s important that users of the app not be able to send out false positives. Covid Watch users are able to choose whether or not to share their results in the app. If you test positive and choose to share your results, public health officials in your area will have access to an online portal to generate a random code that you will need to enter into Covid Watch in order to report a verified positive case. This can be done over the phone, email, or text.
In short, we don’t collect data about who you are, where you go or who you’re near. With the Covid Watch App, your phone periodically sends out what we call Bluetooth chirps, essentially saying to nearby phones, “Hey, I’m here!” If another phone is nearby chirping, “Hey, I’m here too,” both phones will log the interaction and store it for 2-4 weeks right there inside your device. After 2-4 weeks, the interaction is permanently deleted.
If you are diagnosed with COVID-19 , you can choose to share your test results with Covid Watch after they are verified by local health officials. Once you do that, you input a random number into Covid Watch. Immediately, other devices that have recently heard your phone’s Bluetooth chirps will be alerted to a positive result. The alert contains no personal information and no locations. If a hacker broke into Covid Watch, they would just find a bunch of random numbers.
People’s locations, travel history, and contact networks are sensitive personal information that should not be tracked by health authorities or technology companies.
If contact tracing apps store identifying, personal information in a centralized database, there is always a risk that the data will be leaked or hacked. This could expose individuals to scams, identity theft, public shaming, and other negative consequences. It also presents a potential liability for health authorities.
Covid Watch has a privacy-preserving approach. When you use the app, we do not ask you to create a profile or enter in personal information. You can never be identified.
The ACLU favors our decentralized and anonymous approach to using technology to slow the spread of COVID-19 Additionally, we are aligned with a global group of privacy-minded technologists that have coalesced around solutions that protect your privacy and public health at the same time.
Devices that run on the Android operating system require location permissions for apps that access Bluetooth. This is because some apps, but not Covid Watch, use fixed Bluetooth beacons to track location. Covid Watch never tracks your location, even though the multi-layered location control settings in Android may seem confusing. After installing the Covid Watch app you can always verify in your settings that location tracking has not been enabled.
The Covid Watch app stores everything solely on your phone. “Everything” isn’t much—it’s only the random numbers from your phone’s Bluetooth chirps and the log of those you’ve gathered from those around you. No one but you has access to this. If you uninstall the app, your proximity log is gone.
You can choose to share a positive test result by inputting a random generated code into Covid Watch. This code will be generated by the local public health department managing Covid Watch in your area. These random codes aren't meaningful except to the devices which have heard your phone's Bluetooth chirps. The newly alerted phones will ONLY know that they have recently been in proximity with someone who has tested positive.
We can’t identify you because we have never collected information about who you are or where you have been. The communications between phones do not contain any information about who these phones belong to. Covid Watch does not collect personally identifiable information (PII). Exposure notifications can only be generated using a combination of random numbers and the Bluetooth chirps stored on your phone.
We offer a tailored experience based on your needs, and can white label so that your users will see the trusted brand of your public health department, and learn how to get help. If you would like to partner with Covid Watch, request a meeting with our team to learn more.
Apple and Google made a rare joint announcement in April 2020: these two competitors would be working together on creating systems to allow for something they called privacy-preserving exposure notifications’, which is now commonly referred to as GAEN (Google/Apple Exposure Notifications).
Apple and Google responded to challenges Covid Watch and others faced in building a privacy-protecting app to notify communities and individuals of potential exposure to COVID-19.
Read more about Apple and Google’s commitment to privacy here.
Apple and Google built a set of programming tools, called an API, that would allow apps like Covid Watch to more easily use the Bluetooth systems built into billions of smartphones around the world. They will not be building apps themselves.
Instead, the API allows apps like Covid Watch to offer secure and anonymous exposure alert notifications. The Covid Watch app will use these new APIs to offer private solutions to public health problems.
Covid Watch works alongside state, county, and city government health departments. We are a nonprofit, not a government agency. Our mission is to build mobile technology to fight the pandemic while defending digital privacy. The COVID-19 pandemic, however, presents a once-in-a-lifetime challenge to society. Since this crisis began, governments have taken the lead on testing for the virus, issuing stay-at-home orders and manual contact tracing.
The Covid Watch app makes it easier for governments to focus on their role, by narrowing the scope of manual contact tracing and testing efforts. We are working closely with local public health officials to verify testing results and provide them with the tools they need to act quickly.